body {
    min-width: 320px;
    max-width: 750px;
    margin: 0 auto;
    background-color: #F2F4F7;
}
 
a {
     text-decoration: none;
     color: #707070;
}
 
// 约束 当屏幕大于750px的时候 html字体大小不变化
@media screen and (min-width: 750px) {
     html {
         font-size: 37.5px!important;
     }
}

// 顶部
.header {
    height: 2.133333rem;
    line-height: 2.133333rem;
    font-size: .88rem;
    color: #1C1C1C;
    text-align: center;
    border-bottom: 1px solid #EAEAEA;
    background-color: #fff;
}